Komatsu PC490-11, Installation And Instruction Manual

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METHOD FOR CLEANING INSIDE OF COOLING SYSTEM
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WARNING
• Immediately after the engine is stopped, the coolant is still hot and the pressure is accumulated in
the radiator. If the cap is removed under this condition and the coolant is drained, it may cause
burns. Accordingly, wait until the coolant temperature drops, then turn the cap slowly to release the
pressure.
• When starting the engine while cleaning the machine, set the lock lever in LOCK position to prevent
the machine from moving.
• When the undercover is removed, there is a danger of touching the fan.
Never enter in the rear part of the machine when the engine is running.
Place the machine on a level ground when cleaning or changing the coolant.
Clean the inside of the cooling system, change the coolant according to the table below.
Coolant
Cleaning of inside of cooling system and re-
placement of coolant
Non-Amine Engine Coolant
(AF-NAC)
Every 2 year or
4000 hours, whichever comes sooner
The coolant has the important function of preventing corrosion as well as preventing freezing.
Even in the areas where freezing is not an issue, the use of coolant is essential.
Komatsu machines are supplied with Non-Amine Engine Coolant (AF-NAC). Non-Amine Engine Coolant (AF-
NAC) has excellent anti-corrosion, antifreeze and cooling properties and can be used continuously for 2 years
or 4,000 hours.
Komatsu recommends the use of Non-Amine Engine Coolant (AF-NAC). If you use another coolant, it may
cause serious problems, such as corrosion of the engine and aluminum parts of the cooling system.
To maintain the anti-corrosion properties of Non-Amine Engine Coolant (AF-NAC), always keep the density of
Non-Amine Engine Coolant between 30% and 64%.
Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water. When using coolant, investigate the
lowest temperature in the past and decide the density for the coolant from the coolant density table below.
When deciding the density for the coolant, set it for a temperature 10 °C below the actual lowest temperature in
the working area.
The coolant density varies according to the ambient temperature, but it must be over 30% at least.
Coolant density table
Min. atmospheric tem-
perature
°C Min. -10 -15 -20 -25 -30 -35 -40 -45 -50
Density (%) 30 36 41 46 50 54 58 61 64
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WARNING
• Coolant is toxic. When opening the drain valve, be careful not to get coolant on you. If it gets in
your eyes, flush your eyes with large amount of fresh water and see a doctor immediately.
• When handling the cooling water containing coolant that has been drained during changing the
coolant or repair of radiator, contact your Komatsu distributor or request a qualified company to
perform the operation. Coolant is toxic, so never pour it into drainage ditches or drain it onto the
ground surface.
Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water, so it is not flammable.
Check the density with a coolant tester.
MAINTENANCE PROCEDURE MAINTENANCE
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